The US government has ordered BP to provide plans to remove the containment cap after a seep was detected near the ruptured oil well in the Gulf of Mexico.

In a letter to BP boss Bob Dudley, retired Coast Guard Admiral Thad Allen said: “Given the current observations from the test, including the detected seep a distance from the well…I direct you to provide me a written procedure for opening the choke valve as quickly as possible without damaging the well.”

The hydrocarbon seepage could indicate that oil is still leaking from the damaged well on the ocean floor.

Mr Allen demanded that the oil company provide swift action over the latest detected seepage.

“I remain concerned that all potential options to eliminate the discharge of oil be pursued with utmost speed until I can be assured that no additional oil will spill from the Macondo Well.”